Paediatrician and anti-nuclear campaigner Dr Helen Caldicott says her upcoming visit to Roxby Downs will not be part of an ongoing protest against the proposed Olympic Dam mine expansion.

More than 300 protestors have set up camp close to the mine to oppose the export of uranium.

Dr Caldicott will speak to families in Roxby Downs on Wednesday about the health impacts of uranium mining.

She says living near the mine will greatly increase the risk of getting cancer, particularly among children.

"More than half the people in Roxby are children," she said.

"We know that children are extremely radiosensitive. Foetuses are thousands of times more so. One x-ray to the pregnant abdomen doubles the incidence of leukaemia in that child.

"When you come and speak to these communities, the wives tend to get the message and they leave with their families and their husbands, but then more uneducated people move in."

She says radioactive particles become airborne around uranium mines.

"In the dust is radium which is very, very carcinogenic, radon gas and the like so people can be exposed consistently to radon gas which is very nasty stuff... and lots of other isotopes that are all daughters of uranium."

Dr Caldicott says her trip was not intended to coincide with the protests.

"That's serendipity. I was asked to go up there separately," she said.

"I'm going specifically to speak as a doctor."

'Worse than heroin'

Dr Caldicott says Australian uranium was used in the Fukushima reactors that went into meltdown last year.

"I think we need to take responsibility as Australians and much of the uranium in those Fukushima reactors that exposed millions of Japanese to radioactive fallout, that was our uranium," she said.

"We're exporting uranium that gets fission in reactors and becomes one billion times more radioactive.

"Over time our uranium will induce epidemics of cancer.

"It's much worse than exporting heroin because heroin only affects the user whereas this is going to affect all future generations.

"Any country that buys our uranium can make nuclear weapons because 250 kilos of plutonium are made each year in a reactor.

"We are in effect exporting cancer and nuclear weapons and that's not what you would call moral.